A passive optical identification tag that could be read by remote receivers, identified, and authenticated could be useful for several purposes including improved security for homeland security. Applying the tags to vehicles, for example, could aid in tasks such as the remote security control of authorized vehicles inside a restricted area or the control of a vehicle fleet for inventory purposes. Such an identification and verification system would be enhanced if the identification tags were optically encoded so that an accurate image of the code can only be made with sophisticated imaging equipment. Encrypting the code prior to application to the identification tag could provide further security. Such security measures could make it nearly impossible for someone to successfully create a counterfeit identification tag or to capture and decipher the data contained in an existing tag.
Accordingly, an identification tag that can be remotely captured, accurately read and authenticated while also being difficult to copy has potential real world applications.